const mongoose = require('mongoose');
module.exports = new Promise((resolve, reject) => {
    mongoose.connect('mongodb://localhost:27017/student_module', { useNewUrlParser: true, useUnifiedTopology: true, useCreateIndex: true })
    mongoose.connection.once('open', err => {
        if (!err) {
            console.log('数据库连接成功！！');
            resolve();
        } else {
            console.log(err);
            reject(err);
        }
    })
})